I got some free samples of Mr B's Green Tree's and it's the type of product you're looking for. You can soak it in water to make teas, or just spread it on top of your soil as a top dressing and water it in. You'll want to get a veg and a flower tea mix, and I would also get a bag of worm castings or compost for making AACT's. And you will need an air pump/airstone for brewing the teas. It sounds like a lot, but once you get set up, this will free you from bottled nutrients forever.
I'd personally read up on making your own teas from scratch. If you can make cereal with milk, cereal, and sugar, you can make a tea with kelp, alfalfa, and castings. Organics is super simple.